This invention relates to an in-line noise attenuation device for a gas conduit. The device has the ability to cause significant noise attenuation in a conduit without imposing serious restriction to gas flowing through the conduit. The device also has a bi-directional capability that makes it useful both in a situation where the direction of noise propagation through the conduit is the same as that of the gas flow and in a situation where the direction of noise propagation through the conduit is opposite that of the gas flow.
In an automotive vehicle that is powered by a naturally aspirated internal combustion engine, intake air for the engine is sucked through the air induction system. Depending upon the particular engine configuration and manner in which it is operated, noise can propagate back through the air induction system and escape. Too high a level of such noise can be deemed objectionable, and it may therefore become essential to muffle such noise by means of a noise attenuating device. As much as causing significant noise attenuation, it is an equally essential requirement for such a device that it impose no significant restriction on the induction air flow into the engine.
The present invention relates to a new and unique in-line noise attenuation device that complies with the aforementioned requirements of significant noise attenuation and insignificant gas flow restriction. A further attribute of the invention is that it can be conveniently fabricated and installed. Indeed, the preferred embodiment that will be described herein can be fabricated as a single plastic part by conventional plastic blow molding technology. Because usage of the invention is possible in both applications where the direction of noise propagation through a conduit is the same as the gas flow and in applications where the direction of noise propagation is counter to the gas flow, certain principles of the invention have potentially wider application than simply in the application that is to be specifically illustrated and described herein.
Further features, advantages, and benefits of the invention may suggest themselves to the reader as the description proceeds. The accompanying drawing presents a presently preferred embodiment of the invention in accordance with the best mode contemplated at the present time for the practice of the invention as a noise attenuating device for the air induction system of an automotive internal combustion engine.